Locking device



1952 KARL-ERIK G. JOHANSSON 2,620,212

LOCKING DEVICE Filed Dec. 23, 1948 as w 5 m I 4 Lg? Patented Dec. 2, 1952 UNITED STATES ATENT OFFICE LOCKING DEVICE Karl-Erik Gustav J ohansson, Lindesby, Lindesberg, Sweden 4 Claims.

This invention relates toadevice for locking, together at least two members, one of. thembeing movable relative to the other, like, for instance, a rod in a sleeve or a. screw bolt in its hole.

An object of the invention is to create an effective locking element, and to place same .between two striking surfaces in such a way that it expands when being pressed between said striking surfaces.

Another object of the invention is to effect such locking action with a simple device. A third object is to arrange the device so that it may be of all around use in difierent fields, and still another object is to make the lockingprocess itself very simple.

It is true that it has been. suggested earlier (U. S. Patent No. 1,203,071) to use a locking element like a ring inserted between two parts to be locked to one another, but the locking must occur by gradually causing the ring to change from a position at right angles to the axis line of the respective parts, to become more and more oblique, by the actuation of special spring elements.

One object of this invention is to make the device efiective without the aid of a spring element.

Another known device (U. S. Patent No. 2,263,543) endeavors to lock two parts even by means of an intermediary member, but said device is of an entirely different construction than the locking device according to this invention.

Below the invention is described in detail in connection with the attached drawings, which show a number of embodiments of the invention.

Fig. 1 shows a section, axially and longitudinally through the locking device, in this case a rod, movable in a sleeve.

Figs. 2 and 3 show a detail in perspective and axially in section respectively, and Figs. 4 and 5 show other details for this embodiment, shown axially in section.

Fig. 6 shows a section, axially and longitudinal 1y through the locking device, this time applied to a screw connection, and Fig. 7 shows a detail seen from the side for this embodiment.

Figs. 8-10 show other embodiments, axially, in section.

The reference 4 designates the inner part of the rod in Fig. 1, and 3 designates the exterior part or the sleeve in the same figure. This part may of course be made from a pipe of arbitrary length. A slit ring I is placed on the rod and thrust down into an enlargement of the sleeve, and outside the slit ring a screw bushing 2 is screwed into the sleeve 3. The slit ring I is manufactured from a small strip of sheet metal which is cut with a. widev center-portion and tapering end portions bent into the form of a split, ring with top and bottom edges tapering upwardly from the central portion at; angles D. and E, respectively, as shown in Figs. 2 and 3.

In Fig. l the difierent parts are-shown in unlocked position, i. e. the ring I is resting loosely in the sleeve 3. The locking is done iirthefollowing manner:

When the bushing 2 is screwed in thesleevei, the position of the ring I is altered by actuation of the two striking edges 5 and 6, causing the base part B to stand slantwise relative to the other parts of the locking device, as. the ring is pressed against both parts 3 and 4 due. to. a force comparative to the shape and the dimensions of the ring and in proportionto that force which is applied on the screw bushing-in other wordsthe ring expands, and thus makes the locking most efiective.

In the embodiment according to Fig. 6, the inner part, the screw bolt marked as 4a, andthe exterior part, into which the bolt is screwed, is marked 3a. Between the two striking surfaces the ring lb is located, the ring being slit and the side elevation of which can be seen in Fig. 7. The shanks are bevelled so that when the bolt is tightened against the ring, it will, by the action of the striking surfaces 5, 8 change its width, and thus will press against the bolt as well as the inside wall of the sleeve. The harder the bolt is tightened, the more effective becomes the locking.

Fig. 8 shows three parts 3, 4 and 8, which are locked together by means of locking device lc. Part 3, as before, designates a sleeve, part 4 is a rod with shoulder parts 8 and 9 the end of which is threaded. On the threaded part, the threads of which are marked 9a. another rod 8 is screwed which has a corresponding axial screw hole. Between the rod 8 and the shoulder part 6 the locking element I0 is inserted. Although it also in this embodiment consists of a slit ring, it differs from the one in Fig. 6 in that its edges l2, [3 are parallel to one another. The ring can be cut out of a pipe, along two parallel oblique planes. This ring is cut at It. The parts hecome interlocked in that the rod 8 is forced against the ring lc, by being screwed toward the rod 4, and the ring being jammed between the parts 4 and 8, is tipped downward, causing the ring to expand.

The locking ring la shown in Fig. 9 differs somewhat from the one shown in Fig. 8 by being a little more sturdy in appearance, and the striking surfaces la, lb are bevelled. It is forced in between the end surfaces of two sleeves l5, l6

3 situated in a third sleeve l! with which it is in engagement at 2| and 22. Inside the'sleeves l5, 16 there is a rod or spindle 23. When the ring is forced in between the two sleeves [5, Hi, the parts [5, l6, I1, 23, are all interlocked.

Fig. shows how two locking elements, shaped for example as is shown according to Fig. 8, can be combined to effect the locking. They are pressed between two striking surfaces [8, l9 analogous to what has been shown in Fig. 9. They may, as the drawing shows, touch each other.

This locking device may be used in many different ways. The embodiment according to Fig. 1 may be used for camera standards, music racks, lamp stands, just to name a few examples, and as for the embodiment shown in Fig. 6, the member 3a does not merely represent a fixed part of a machine, into which the bolt is screwed, but also a nut screwed on to the screw bolt. Thus the embodiment according to Fig. 6 may also be used in many different ways. The rods shown in the drawing may also constitute rotatable spindles.

It will be obvious that various changes may be made in form and construction of the par-ts without departing from the spirit and scope of the invention, or sacrificing any of its material.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A locking device for securing inner and outer cylindrical members having spaced cylindrical surfaces forming an annular chamber therebetween, one of said surfaces terminating in a shoulder forming one end of said annular chamber, an axially movable member in the annular chamber between said surfaces and having a shoulder forming the other end of said chamber, and a ring disposed in said chamber, said ring being cylindrical in form with two opposite sides axially offset and engageable by the respective shoulders to tilt said ring toward a plane normal to the axis of said cylindrical members in response to '4 axial movement of said last member, one of said sides having an axial width greater than the spacing between said cylindrical surfaces so that the opposed edges thereof engage and exert a clamping action upon said cylindrical surfaces when said side is tilted, the other of said sides being sufliciently narrow in the axial direction to pass freely between said cylindrical surfaces when tilted, whereby the side pressure of the first side of said ring serves to wedge said cylindrical members together,

2. A locking device, as set forth in claim 1, in which said ring is formed at said narrow side with a slit to form a pair of resilient shanks tapering in width from the wide side of said ring to the ends of said shanks, said slit being of a width to provide clearance for contraction of said ring under the clamping pressure of said shoulders.

3. A locking device, as set forth in claim 1, in which said cylindrical members comprise a rod and sleeve, said first shoulder being formed on said sleeve and said axially movable member being carried by said sleeve.

4. A locking device, as set forth in claim. 1, in which said inner member comprises a bolt screwable in said outer member, said first shoul der being formed in said outer member and said second shoulder being formed on said bolt.

KARL-ERIK GUSTAV J OHANSSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,326,623 Voight Dec. 30, 1919 2,322,949 Lux June 29, 1943 2,430,649 Schulz Nov. 11, 1947 FOREIGN PATENTS Number Country Date 12,103 Great Britain June 20, 1893 

